Unless you put a pressure tester in the line, (special connector to the front tensioner hole), you can't know what the pressures are.
They should be; min. 0.8 bar at 1500 rpm.
min. 2.4 bar - max. 3.5 bar at 6000 rpm.

I've found that different oils do make the engine sound different, so before you tear into it, drain your oil, check to see there is nothing on the sump plugs magnets and then try going to the thicker oil and see.

But other than that, I don't have much more.

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I often wonder where that road goes? And that, has usually made all the difference. Appologies to Mr Frost

Thanks again Kamaya. I have rechecked again my cam timing, valve clearance and bridge bolt torque. Guess I'll change the oil and see what is sounds like. I haven't yet pulled the ignition cover to see that end of the balance shaft. Anything there to be checked??

Thanks again Kamaya. I have rechecked again my cam timing, valve clearance and bridge bolt torque. Guess I'll change the oil and see what is sounds like. I haven't yet pulled the ignition cover to see that end of the balance shaft. Anything there to be checked??

The only thing on that side is the balance shaft seal in the cover. It has been found to play a crucial role in the amount of oil that makes it into the breather pipe and subsequently overboard through your front carb. This however has a marginal effect on oil pressure and I don't think has anything to do with your symptoms.

The cover can be a bit of a pain as there are big magnetic forces, tight frames space and delecate cover gasket. A trick, I learnt on here I think, is putting a few zipties through the covers' bolt holes and into the corresponding case holes to act as guides and keep the gasket in place whilst mounting.

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I often wonder where that road goes? And that, has usually made all the difference. Appologies to Mr Frost